JavaWeb学习-MVC基础开发系列-5-用户注册校验实现

r囧r小猫 2022-04-25 09:00 225阅读 0赞

这篇来看看用户注册表单中，如果用户数输入内容和字段要求不符合，弹出对应错误消息提醒。这个过程要怎么实现呢，

**1.新写一个实体类**

这个实体类，就是一个UserForm.java，里面包含注册表单的一切属性，还有一个map集合，用来存放各种错误提示。

package com.anthony.domain;
    
    import java.io.Serializable;
    import java.text.ParseException;
    import java.text.SimpleDateFormat;
    import java.util.HashMap;
    import java.util.Map;
    
    public class UserForm implements Serializable {
    	
    	private String username;
    	private String password;
    	private String repassword;
    	private String email;
    	private String birthday;
    	private int id;
    	
    	
    	private Map<String, String> msg = new HashMap<String, String>();
    	
    	public boolean validate() {
    		//校验用户名输入
    		if("".equals(username)) {
    			msg.put("username", "用户名不能为空");
    		}else if(!username.matches("\\w{3,8}")) {
    			msg.put("username", "用户名为3—8位字母组成");
    		}
    		//校验密码输入
    		if("".equals(password)) {
    			msg.put("password", "密码不能为空");
    		}else if(!password.matches("\\d{3,8}")) {
    			msg.put("password", "密码为3—8位数字组成");
    		}
    		//校验两次密码输入是否一致
    		if(!repassword.equals(password)) {
    			msg.put("repassword", "两次输入密码不一致");
    		}
    		
    		//邮件规则正则
    		if("".equals(email)) {
    			msg.put("email", "邮箱不能为空");
    		}else if(!email.matches("^[A-Za-z\d]+([-_.][A-Za-z\d]+)*@([A-Za-z\d]+[-.])+[A-Za-z\d]{2,4}$")) {
    			msg.put("email", "不是有效的邮箱格式");
    		}
    		
    		//生日输入规则
    		if("".equals(birthday)) {
    			msg.put("birthday", "生日不能为空");
    		}else {
    			SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
    			try {
    				sdf.parse(birthday);
    			} catch (ParseException e) {
    				msg.put("birthday", "请输入正确邮箱格式");
    			}
    		}
    		return msg.isEmpty();// 当集合为空，全部条件验证通过，返回true
    	}
    	
    	public Map<String, String> getMsg() {
    		return msg;
    	}
    
    	public void setMsg(Map<String, String> msg) {
    		this.msg = msg;
    	}
    	
    	public String getUsername() {
    		return username;
    	}
    	public void setUsername(String username) {
    		this.username = username;
    	}
    	public String getPassword() {
    		return password;
    	}
    	public void setPassword(String password) {
    		this.password = password;
    	}
    	public String getRepassword() {
    		return repassword;
    	}
    	public void setRepassword(String repassword) {
    		this.repassword = repassword;
    	}
    	public String getEmail() {
    		return email;
    	}
    	public void setEmail(String email) {
    		this.email = email;
    	}
    	public String getBirthday() {
    		return birthday;
    	}
    	public void setBirthday(String birthday) {
    		this.birthday = birthday;
    	}
    	public int getId() {
    		return id;
    	}
    	public void setId(int id) {
    		this.id = id;
    	}
    	
    	
    
    }

这里提醒一下，如果msg不写成属性字段，然后添加set和get方法，那么会报错误：with root cause  
javax.el.PropertyNotFoundException: Property \[msg\] not found on type \[com.anthony.domain.UserForm\]

**2.修改RegServlet.java**

package com.anthony.web.servlet;
    
    import java.io.IOException;
    import java.util.Date;
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import org.apache.commons.beanutils.BeanUtils;
    import org.apache.commons.beanutils.ConvertUtils;
    import org.apache.commons.beanutils.locale.converters.DateLocaleConverter;
    
    import com.anthony.domain.User;
    import com.anthony.domain.UserForm;
    import com.anthony.service.UserService;
    import com.anthony.service.impl.UserServiceImpl;
    
    
    public class RegServlet extends HttpServlet {
    
    	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    		req.setCharacterEncoding("UTF-8");
    		resp.setContentType("text/html;charset=UTF-8");
    		//获取表单数据
    		UserForm uf = new UserForm();
    		try {
    			BeanUtils.populate(uf, req.getParameterMap());
    		} catch (Exception e1) {
    			e1.printStackTrace();
    		}
    		
    		if(!uf.validate()) { //如果msg map集合不为空，说明输入条件不符合要求
    			req.setAttribute("uf", uf);
    			req.getRequestDispatcher("/register.jsp").forward(req, resp);
    			return; //出错，不需要往下走注册流程，所以这里需要return空来终止代码往下执行
    		}
    		
    		User user = new User();
    		try {
    			//解决日期是字符串的异常
    			ConvertUtils.register(new DateLocaleConverter(), Date.class);
    			BeanUtils.populate(user, req.getParameterMap());
    			//调用业务层方法/逻辑
    			UserService us = new UserServiceImpl();
    			us.register(user);
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		
    		//分发转向
    		resp.getWriter().write("注册成功，2秒之后跳转到主页");
    		resp.setHeader("refresh", "2;url="+req.getContextPath()+"/index.jsp");
    	}
    
    	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    		doGet(req,resp);
    	}
    	
    	
    
    }

**3.修改register.jsp**

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>注册</title>
    </head>
    <body>
    	<form action="${pageContext.request.contextPath}/servlet/regServlet" method="post">
    		用户名：<input type="text" name="username" value="${uf.username}"/>${uf.msg.username}<br/>
    		密码：<input type="password" name="password"/>${uf.msg.password}<br/>
    		确认密码：<input type="password" name="repassword"/>${uf.msg.repassword}<br/>
    		邮箱：<input type="text" name="email" value="${uf.email}"/>${uf.msg.email}<br/>
    		生日：<input type="text" name="birthday" value="${uf.birthday}"/>${uf.msg.birthday}<br/>
    		<input type="submit" value="注册">
    	</form>
    </body>
    </html>

4.测试效果

4.1 全部为空

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE1NDE5NDY_size_16_color_FFFFFF_t_70][]

4.2 名称和密码不符合3-8规则

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE1NDE5NDY_size_16_color_FFFFFF_t_70 1][]

4.3 生日不符合规则

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE1NDE5NDY_size_16_color_FFFFFF_t_70 2][]

上面邮箱格式判断明显有问题，说明这个正则表达式写的有问题。以后实际开发中，可以网上搜一下，别人是如何写邮箱地址判断的正则表达式。

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE1NDE5NDY_size_16_color_FFFFFF_t_70]: /images/20220125/49c0d95bf8bb4fbdae3da422a92a3497.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE1NDE5NDY_size_16_color_FFFFFF_t_70 1]: /images/20220125/a8aaaff401444929a42978ee21d6fc0e.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE1NDE5NDY_size_16_color_FFFFFF_t_70 2]: /images/20220125/aad5ed2afaab451da8871c9545699f4c.png